This invention relates to the field of colorant pumps and, in particular, to a modular automatic colorant dispenser.
Automatic Colorant Dispensers are well known in the art. Generally, colorants dispensed by these dispensers contain various abrasive and corrosive components including water. The prior art pumps used to dispense these colorants are of a lower quality, generic, single impeller xe2x80x9coil-pumpxe2x80x9d type usually produced from cast iron and are continuously exposed to the abrasive, oxidizing materials. These operating conditions cause dramatic wear to critical internal metering components in the generic prior art pumps resulting in their eminent failure usually within the first three months of normal system usage. These prior art pumps are very inconvenient to replace in existing prior art automatic colorant dispensers because of antiquated drive methods employed. These pumps are also very expensively priced and including the required qualified service technician labor, pump replacement can initially cost up as much as one tenth of the total system price.
Prior art pumps were never originally designed to pump colorants. Prior art pumps handled many different types of oils. These oils provided the much needed shaft lubrication.
Because pumped colorants do not provide any lubrication, constant colorant abrasion under pressure attacks the solid cylindrical bearings needed to maintain the proper pump shaft rotational geometry in all prior art pumps. The prior art pump drive system torque requirements are extremely demanding, highly inefficient and drive up the overall electrical power requirements of the entire automatic colorant dispenser. A single prior art pump cannot be rotated manually indicating the extremely inefficient method of pump shaft bearing design.
Attempting to protect and to reduce the internal wear and damage caused by the hardened foreign matter in colorants, generic prior art pumps employ a ceramic plastic impeller. This material has proven to be a poor design choice for the application. Broken or chipped impeller teeth cause severe loss of calibration and reduce the pump output dramatically.
Prior art automatic dispenser manufacturers have also implemented individual colorant filters or strainer units attempting to protect their pumps from the foreign materials in the colorants. Because of the wide viscosity ranges of many popular colorants, the filters or strainers almost immediately clog up and starve their pumps of colorant. Because precise, repeatable metering is needed to deliver each colorant to achieve the desired color formula or recipe, the clogging causes the product to be mis-tinted and ultimately rejected.
Prior art dispensers usually contain from ten to sixteen colorant circuits each including one storage canister and one pump per colorant circuit. Prior art pumps are driven by either one of two ways.
The first method employs a large length of roller chain, associated idler sprockets to maintain chain positioning through the dispenser and a large horsepower motor with a gear reduction unit that provides the needed output power.
The second method is employing an individual motor of significant fractional horsepower with a combined gear reducer to an individual prior art pump with horizontal shaft rotation. The majority of prior art automatic dispenser manufacturers all have chosen the single roller chain driven approach over of the large expense of multiple drive motor/gear reducers. Both of these drive approaches sacrifice individual precision metering because the prior art pumps were never designed to deliver dispense accuracies greater than {fraction (1/128)} of an ounce.
Replacement of pumps in the prior art has been difficult due to the pump locations and the critical realignment of these drive components must be completed in cramped confined space which is very time consuming. This intentionally reinforces that prior art pumps should only be replaced by factory approved service technicians.
Canisters of the prior art automatic dispensers have been produced from stainless steel tube with welded bottom plates. Each colorant canister in a system contributes significant weight to the system. In configuring prior art automatic dispensers to dispense water-based colorants for architectural paints and coatings, stainless steel canisters provide no significant structural advantages and could actually be replaced with other equally compatible canister materials such as PVC (polyvinylchloride) that are lighter and more easily machined.
Automatic dispensers in the prior art utilize a discharge nozzle component that allows each individual colorant circuit to come together in a small diameter. The prior art nozzles have many mechanical joints where components must be connected at mating surfaces. O-rings are needed to seal each joint. Every joint is a potential location for colorant to leak between individual circuits causing cross contamination of all of the colorants.
Automatic Dispensers in the prior art have been manufactured for over forty years using large, space consuming cabinets weighing in excess of a half ton with bulky roller conveyors attached to the front sections. Prior art cabinets were never efficiently designed for functional usage in providing adequate service access openings to critical internal components. Prior art dispenser manufacturers physically buried computers inside prior art cabinets eliminating the possibility of quick access or even simple upgrading of the operating PC system. For these types of customer service, an authorized factory service technician would be required to perform these tasks.
For many years, the Paint and Coatings market has been requesting smaller, more compact cabinets to fit the constantly shrinking floor space availability faced by paint retailers and manufacturers. Prior art manufacturers have responded to these requests only with automatic dispenser designs that suffer decreased performance and reliability to insure that their customer service departments maximized profitability.
Automatic dispensers in the prior art have always required the refilling of each of the colorant canisters. Prior art manufacturers have made the colorant refilling process a difficult task by placing certain canisters in extremely hard to reach locations. In some models, half of the colorant canisters used are at the rear of the dispenser making access to those canisters impossible. Prior art dispensers have been poorly designed with the addition of heavy, hard to move roller conveyors that span the entire front of the dispenser cabinets.
Prior art manufacturers have not addressed the serious ergonomic needs of the operator for the safe operation and maintenance of prior art automatic dispensers. Operators place themselves in potentially harmful physical positions when attempting to reach the inaccessible rear mounted canisters. Operators must straddle the bulky, front mounted roller conveyor in the refilling process while pouring heavy containers of colorant at arms length.
Addressing the electrical requirements and associated electronics of existing automatic dispensers in the prior art have basically operated in the very same way for as long as they have been manufactured. Presently offered systems operate using inefficient large horsepower motors to handle the demanding torque requirements of each out of date pump. Safety is an issue when trying to replace or repair a component that may be near any one of unguarded exposed roller chain paths. It is important to note that these systems have not improved with modern cutting edge technology, either in mechanical advances or in innovative electronics.
The present invention includes a specifically designed pump module, containing a precision dual bearing housing with two pairs of precision needle bearings, hardened dual shafts and impellers, an abrasion resistant, hard-coated pump chamber, twin Viton cartridge seals, an abrasion resistant, hard-coated lower cover plate and premium quality, quick disconnect fittings at inlet and outlet of pump chamber.
The present invention incorporates the pump, mounted on a pump drive bracket with power provided to the main pump shaft by a precisely controlled stepper motor. The stepper motor is directly connected to the driven pump shaft with a zero backlash coupling of solid design. The stepper motor is mounted to the top surface of the pump drive bracket providing simple but precise alignment of all three components. The pump module is physically attached to the base of the modular cabinet with a new 3M product that provides easy attachment, but this 3M foam adhesive product also cushions and eliminates vibrations and provides absolute silence during operation.
Therefore, it is an aspect of the invention to provide an efficient colorant pump with repeatable high accuracy.
It is another aspect of the invention to provide a colorant pump that delivers superior extended life.
It is still another aspect of the invention to provide a colorant pump that requires minimal torque to rotate.
It is a further aspect of the invention to provide a precisely supported bearing shaft geometry that will not fail under constant colorant pressure or contamination.
It is yet another aspect of the invention to provide an automatic colorant dispenser that has maximized modular design geometry and provides efficient, simplified repair or replacement of all critical parts.
It is still another aspect of the invention to provide an automatic colorant dispenser that operates quietly.
The present invention also incorporates a specifically designed canister module that is mounted in an ergonomic space-saving cabinet. The modular automatic colorant dispenser includes mounting provisions for up to sixteen canister modules. The canister modules are produced from PVC and have a lower plate and upper cover also fabricated from PVC. Each canister module is directly mounted to the top mounting plate surface in the new modular cabinet. Each pump module is directly positioned under each canister module to optimize the input connection tubing geometry between pump and canister. No colorant filters or strainers are required or used in the present invention.
Each canister module includes a built-in colorant agitator motion system. An individual agitator motor is connected to the bottom plate of each canister. A center pipe is threaded into the canister bottom plate with a Viton o-ring sealing the threaded pipe connection. The center pipe is fitted with small bearings at the top and bottom of the pipe. The agitator shaft rotates inside the center pipe and directly connects to the agitator motor output shaft.
The specifically designed ladder fin agitator provides slow, gentle agitation of all colorants and is fully programmable to handle even the most demanding colorants. The canister module has been designed to allow simplified replacement by removing four screws in the top mounting plate and disconnecting the inlet, outlet lines and unplugging the electrical connection to the agitator drive motor.
The present invention also incorporates each component module into a specifically designed modular automatic dispenser cabinet. The modular cabinet has been designed to efficiently house all automatic dispenser component modules. Up to sixteen colorant canister positions have been arranged in twin hexoidal canister patterns to reduce total cabinet space. Easy access to all system components modules has been provided through four (4) full width panels. One panel each on the left and right sides and two panels at the rear allow maximum open access of all dispensing components. Each panel is the same physical size and is fitted with a keyed lock.
The present invention incorporates additional features into the modular automatic dispenser cabinet that provide safety to the operator. Two hinged top panels provide full open access to all colorant canisters for easy refilling of colorants. Both left and right side panels are equipped with air dampened shock cylinders to eliminate any possibility of premature panel closing. Both panels will safely remain in a vertical position until the operator physically closes the top panels.
The present invention incorporates a centrally located compartment that houses up to sixteen individual solenoid valves. The forward, upper central cabinet location for these valves is critical in maintaining a minimal length of output tubing between each colorant circuit solenoid valve and their corresponding discharge nozzle connection.
The modular automatic dispenser cabinet has been designed with a small cabinet protrusion at the upper front center area that houses a discharge nozzle module of compact geometry. All required colorants to produce a specific paint formula can be simultaneously dispensed from this compact discharge nozzle module without any opportunity of colorant contamination between colorant circuits.
Each colorant circuit in the discharge nozzle module is equipped with a quick disconnect fitting allowing direct connection to each solenoid valve with an absolute minimal length of tubing. The modular automatic colorant dispenser cabinet provides a removable discharge nozzle module cover for full access to this modular component. A flush mounted upper cover is also provided for full access to the complete solenoid valve array and the associated colorant circuit tube piping.
It is another aspect of the invention to provide an automatic colorant dispenser with a nozzle that does not leak or drip.
The present invention incorporates two built-in retractable, stainless steel shelves for simplified dispensing of colorants into both one (1) gallon containers and also five (5) gallon buckets. When retracted, both shelves are flush to the front surface of the modular cabinet. The five gallon shelf has been designed into a flush mounted opening is the full width of the cabinet.
A specifically designed spring loaded, locking latch mechanism is centrally located below the five gallon shelf The two-piece locking arm is fabricated from multiple laminated steel plates for maximum strength. The locking latch design provides positive locking of the shelf in the operating position and can withstand four times the actual load.
The simple lifting of the shelf allows the spring-loaded detent to release the shelf for flush mounted storage. This detent is automatically reset when the shelf is lowered, allowing the next locking motion to occur.
The stainless steel working surface of the five (5) gallon shelf has been formed with three full width horizontal ribs to assist in the movement of five (5) gallon pails and totally eliminates the need of bulky, space consuming conveyor rollers. When placed in the appropriate dispense position on this shelf, with the filler cap or xe2x80x9cbung holexe2x80x9d opened, a five (5) gallon pail will maintain precise alignment to simultaneously receive the required colorants.
The one (1) gallon shelf is located above the five (5) gallon shelf and flips down to provide a solid stainless steel work surface for processing up to three one (1) gallon containers. When this shelf is flipped up, the shelf becomes flush to the cabinet front surface. When placed in the appropriate dispense position on this shelf, with the can lid removed, a one (1) gallon can will maintain precise alignment to simultaneously receive the required colorants.
It is another aspect of the invention to provide an apparatus for connecting a support shelf to a work surface that maintains space efficiency.
The present invention also incorporates a flush mounted access panel cover located between the one (1) gallon shelf and the cabinet mounted discharge nozzle module. This front access panel may be removed to access the entirely self-contained electronics bay.
The flush mounted electronics bay is a steel fabrication that houses all of the electronic components that provide signals and power to each internal module. This includes a compactly designed printed circuit board rack with individual printed circuit cards controlling internal processing, power management and digital switching functions. This electronics bay also houses up to sixteen stepper motor controller cards that individually control each stepper-motor driven pump module.
The electronics bay has also been designed to fully comply with all applicable emission regulation and safety compliance guidelines and to provide the required airflow ventilation needed to maintain the appropriate electrical component environment. The electronics bay access cover is secured with six hex flathead fasteners.
The present invention also incorporates heavy-duty swivel casters at each corner of the modular automatic colorant dispenser cabinet for easy positioning. Two heavy-duty levelers are provided, one at each side near the front edge of the modular cabinet to maintain maximum stability of the modular automatic colorant dispenser after proper positioning has taken place.
The present invention incorporates the stepper-motor driven pump modules, the colorant conditioning canister modules, the solenoid valve array module and discharge nozzle module into a compact, space saving 24xe2x80x3xc3x9748xe2x80x3 footprint that weighs approximately half of all prior art systems. Each individual sub-system module can be easily accessed for inspection or replacement with ultimate simplicity.
The present invention incorporates a low-profile computer tray that glides from left to right over each of the upper cabinet top panels. The computer tray is fabricated from lightweight aluminum and contains eight (8) miniature rollers that allow effortless movement of the personal computer (PC), monitor, keyboard, mouse and other peripherals. A rear mounted tethered cable limits the overall travel of the computer tray. The tray provides full access to either of the two top panels for colorant refilling procedures but does not use valuable space inside the modular automatic dispenser cabinet.
It is another aspect of the invention to provide a cabinet for a modular automatic dispenser that is space and weight efficient.
The operating sequence for this system occurs as follows. The external PC communicates to the internal digital controller via standard RS-232C communications protocol and instructs the automatic colorant dispenser as to which colorants and in what amounts are to be delivered for each dispensing cycle. When the container is placed in the appropriate position on the appropriate shelf, the operator presses the dispense button on the keyboard. The digital controller activates each of the required colorant circuit valves and each of the required stepper-driven colorant pumps to simultaneously dispense all colorants into the container. Depending on the specific formula and container size, new FlowMaster pumps accurately and repeatabily dispense formulas in as little as five seconds up. The tinted container is then removed from the shelf, re-sealed or re-capped and then thoroughly mixed.
Colorants are automatically recirculated throughout each colorant canister circuit by programming into the pc, a specific amount of appropriate recirculation. The pump modules are gravity fed colorant from each canister module and if a specific colorant has not been chosen for a considerable amount of time, the pump module will activate and pump the respective colorant through the pump, up to the respective solenoid valve, and back to the upper return fitting of each canister.
For normal periods of inactivity, each colorant canister will engage the agitator drive that is built into each canister. The agitator drive provides a gentle six (6) rpm stirring motion to the colorant and the specially designed ladder fins rotationally raise the heavier materials, which want to settle to the bottom of the canister. This gentle motion is also programmably controlled. For extended periods of inactivity, a discharge nozzle cover or cap is provided to seal off air from each individual colorant circuit in the discharge nozzle module.
It is another aspect of the invention to provide an automatic colorant dispenser that efficiently operates all sub-systems using low voltage D.C. power components for maximum energy efficiency.
These aspects of the invention are not meant to be exclusive and other features, aspects, and advantages of the present invention will be readily apparent to those of ordinary skill in the art when read in conjunction with the appended claims and accompanying drawings.